A Fidelity Investments analysis shows 401(k) and IRA balances are at record highs. / Getty Images/iStockphoto

by Nanci Hellmich, USA TODAY

by Nanci Hellmich, USA TODAY

The bull market has sent 401(k) retirement plan balances soaring to record highs, according to an analysis by Fidelity Investments released today.

Fidelity analyzed its accounts for 13 million workers with 401(k) plans as well as its IRA balances for individuals at the end of the second quarter. Among the findings:

â?¢ The average 401(k) balance rose 12.9% to $91,000, a record high, up from $80,600 at the end of the second quarter of 2013. This represents accounts from a wide range of workers, including those just starting their careers and others nearing retirement.

â?¢ The average balance in a Fidelity Individual Retirement Account (IRA) at the end of the quarter was $92,600, another record high, up 14.7% compared with the same time last year.

â?¢ 77% of the growth in account balances is due to the stock market; 23% is due to employee and employer contributions.

â?¢ The average balance for employees who have been saving in their 401(k) for 10 years increased 15% over the last decade to $246,200.

â?¢ Employees contributed an average of $6,050 to their 401(k)s this past year; employers contributed an average of an additional $3,540.

Since 2010, average employee contributions have increased $470, and average employer contributions have gone up $400 for an overall increase of $870 during that four-year period, says Fidelity Investments Vice President Jeanne Thompson.

She says 401(k)s are "the primary retirement vehicle for most American workers, so it's encouraging to see both employees and employers socking away as much as possible."

It has been great to see the market rising, but on Thursday it went down, Thompson says. This is a good time to check your assets and make sure you're comfortable with your investments.

Some people have 100% of their portfolio in stocks and stock mutual funds, and others have nothing in them, Thompson says. "Neither is a good plan," she says.

If you are 100% invested in stocks and stock mutual funds, you are taking on too much risk, she says. "Similarly, if you have no money in stock mutual funds, you might not earn enough to keep up with inflation."

People who do not have "the will, the skill or the time to manage their retirement investments might benefit more if they had professional management," Thompson says. "You have to turn your 401(k) into a retirement paycheck, and small changes and keeping tabs on it can make a big difference in the long run."